LGP Science Thread

[Shyster]

The initial Falcon 1 test vehicle was developed with private money—something like $100 million from Musk himself. NASA money did help pay for the development of the Falcon 9, but certainly not all of it and not up front. And I dispute them being "almost still almost entirely dependent upon government contracts at this stage." SpaceX has as many if not more private launches on the manifest than government launches, and the Boca Chica facility in Texas is being developed almost exclusively for private-sector launches to GTO. By contrast, the Atlas and Delta are pretty much used exclusively for government launches because they can't compete price-wise with other options like SpaceX, Arianespace (Ariane 5 and Vega), and Roscosmos (Proton and Soyuz).

[shafnutz05]

So we know that the drought is California is very bad (speaking of which, is the Crown City of Hypocrisy, San Francisco, finally conserving water?). Last I heard they were still blissfully immune from any type of mandatory conservation.

At any rate, why are there only three desalination plants from the Bay Area to the Mexican Border? I would think in an area so prone to drought, this would have been thought out by now?

[PensFanInDC]

My mother in law used to work for the water authority in San Diego. She might know. Ill ask her.

[PensFanInDC]

So we know that the drought is California is very bad (speaking of which, is the Crown City of Hypocrisy, San Francisco, finally conserving water?). Last I heard they were still blissfully immune from any type of mandatory conservation.

At any rate, why are there only three desalination plants from the Bay Area to the Mexican Border? I would think in an area so prone to drought, this would have been thought out by now?

Quick list from her:

Super expensive
Intrusive on environment (endangered algae you know...)
A lot of people don't want them
Takes up a lot of land

[tifosi77]

Perhaps they have not previously instituted restrictions because SF residents use - by far - the least amount of water per capita of all CA cities. Part of that is driven by the climate (mild, always foggy), and part of that is driven by the fact that there are few residences with yards/lawns within the city.

Who uses how much? California water by the numbers

Of course, that's a four-year old report by the Bay Area chapter of the Sierra Club. But it appears to still be more or less accurate.

California Drought: Database shows big difference between water guzzlers and sippers

As regards desalination: It is an expensive process; the cost is roughly double per gallon vs building a reservoir, and I've read nearly four times as costly as basic conservation methods. It also poses some pretty aggressive environmental challenges, and it's not the most efficient process (roughly half the water is lost in the de-salting process). There's a new desalination plant that just opened in Carlsbad (about halfway between here and San Diego), and people are looking to see how that goes before any decisions are made regarding the dozen or so other proposed desalination plants.

[columbia]

Might as well work out the kinks now, because they'll really be needed in 50 years. Thankfully, I won't be around.

[Willie Kool]

I tend to believe that the Big Bang was/is being fueled by past/present/future black holes in our own universe.

Any reason to back up that belief?

Occam's Razor. If we don't need unobservable multidimensional universes to explain something, why go there? That said, I do find string theory fascinating and actually quite intuitively appealing, so I'm not really opposed to their conclusion.

These theories exist because we DO need them to explain things. How do you explain exact values like the cosmological constant...

Exact value? Which one? Last I knew, they were still 51 orders of magnitude away from matching observation.

Not sure how that deduction is a valid application of Occam's Razor.

I don't believe it is necessary to call upon extra dimensional parallel universes to explain the Big Bang.

Do we know where (when ) all the matter that falls out of our universe goes? Do we know that all the matter in the universe won't eventually end up there (then)?

Until I'm shown proof, I'll take the simpler explanation.

[DontToewsMeBro]

Do we know where (when ) all the matter that falls out of our universe goes? Do we know that all the matter in the universe won't eventually end up there (then)?

I'm not exactly sure what you mean by "falls out" since black holes aren't really 'holes'. Are you familiar with the holographic principle proposed by Hooft? It states that the informational content of the volume of an object can be thought of as encoded on its manifold. As it relates to black holes, anything that "falls into" a black hole is preserved on its event horizon to an outside observer.

[Willie Kool]

anything that "falls into" a black hole is preserved on its event horizon to an outside observer.

And there's the rub. We can't really know from outside.

[DontToewsMeBro]

anything that "falls into" a black hole is preserved on its event horizon to an outside observer.

And there's the rub. We can't really know from outside.

Yes but we really don't understand the physics that goes on "in" a black hole, at least at the singularity. I don't prescribe to the Fecund universe theory as you do (black holes lead to creation of other universes) but it's been around for a while since Lee Smolin popularized the idea in the 90s, and hasn't gotten much recognition from the community for some reason.

[Shyster]

Perhaps they have not previously instituted restrictions because SF residents use - by far - the least amount of water per capita of all CA cities. Part of that is driven by the climate (mild, always foggy), and part of that is driven by the fact that there are few residences with yards/lawns within the city.

Plus it's full of hippies, and there's a reason hippies are stinky.

[columbia]

Perhaps they have not previously instituted restrictions because SF residents use - by far - the least amount of water per capita of all CA cities. Part of that is driven by the climate (mild, always foggy), and part of that is driven by the fact that there are few residences with yards/lawns within the city.

Plus it's full of hippies, and there's a reason hippies are stinky.

There's far more homeless people than hippies. In fact, I don't think there's very many hippies in SF, these days.

[thehockeyguru]

Perhaps they have not previously instituted restrictions because SF residents use - by far - the least amount of water per capita of all CA cities. Part of that is driven by the climate (mild, always foggy), and part of that is driven by the fact that there are few residences with yards/lawns within the city.

Plus it's full of hippies, and there's a reason hippies are stinky.

There's far more homeless people than hippies. In fact, I don't think there's very many hippies in SF, these days.

They cant afford it.

[Willie Kool]

I don't prescribe to the Fecund universe theory as you do (black holes lead to creation of other universes) but it's been around for a while since Lee Smolin popularized the idea in the 90s, and hasn't gotten much recognition from the community for some reason.

I've been out of school since the early 90's, and had never heard of Smolin or his theory. It does appear to be a bit similar to what I believe, except in his theory the black holes form multiple new universes where I think the breakdown of time allows for all black holes in our universe (past, present and future) to feed back into the original Big Bang.

I do like this quote: "More and more, I have the feeling that quantum theory and general relativity are both deeply wrong about the nature of time. It is not enough to combine them. There is a deeper problem, perhaps going back to the beginning of physics."

[DontToewsMeBro]

If you have time I'd suggest reading his relatively new book Time Reborn. Not exactly 'light' reading but it has little math and a lot of very novel ideas about time's role in physics. It caused quite a stir in the physics community, which I think is always a good thing.

[PensFanInDC]

What if c-a-t really spelled dog

[Kaizer]

anything that "falls into" a black hole is preserved on its event horizon to an outside observer.

And there's the rub. We can't really know from outside.

Time slows for the matter being taken in, so why would any of it actually make it to the singularity? Maybe nothing pulled into a black hole has ever made it there since the black hole formed, thus it wouldnt exit the universe, or do anything else that could happen when it becomes part of the object's mass, since it never has and never will join completely.

[Willie Kool]

Time slows for the matter being taken in, so why would any of it actually make it to the singularity?

Gravitational time dilation only makes it APPEAR TO AN OUTSIDE OBSERVER as if time slows for matter approaching the event horizon. The matter itself doesn't actually slow down.

[DontToewsMeBro]

Time slows for the matter being taken in, so why would any of it actually make it to the singularity?

Gravitational time dilation only makes it APPEAR TO AN OUTSIDE OBSERVER as if time slows for matter approaching the event horizon. The matter itself doesn't actually slow down.

This is correct, which is why to an observer the information falling into a black hole is preserved on its event horizon, so it doesn't violate the laws of thermodynamics (as Hawking incorrectly assumed for many years). However, whatever happens at the singularity is anyone's guess as our current understanding of physics breaks down (as it does with the Big Bang). A lot of physicists believe either our interpretation of physics is wrong (GR + QM), or there aren't truly singularities in the universe.

[Kaizer]

Youve just blown me.

My mind, i mean.

[Willie Kool]

[youtube][/youtube]

[count2infinity]

[youtube][/youtube]

[stopper40]

http://www.iflscience.com/physics/cryst ... -potential" onclick="window.open(this.href);return false;

[count2infinity]

wtf has Nasa done to make your life awesome?

http://wtfnasa.com/" onclick="window.open(this.href);return false;

[columbia]

Should We All Take a Bit of Lithium?
http://www.nytimes.com/2014/09/14/opini ... thium.html" onclick="window.open(this.href);return false;